Since early 2006, highly pathogenic avian influenza H5N1 has been clocking up air miles at an alarming rate. It has spread quickly to Europe, the middle east, India, and Africa following no apparent pattern, and underlining how little scientists know about the virus ecology and where it will strike next. There is now growing concern that the whirlwind spread of avian flu in some parts of the world is not entirely governed by nature, but by the human activities of commerce and trade. Since mid-2005, the Food and Agriculture Organisation (FAO) and WHO have given wide prominence to the theory that migratory birds are carrying the H5N1 virus and infecting poultry flocks in areas that lie along their migratory route. Indeed, this is probably how the virus reached Europe. Unusually cold weather in the wetlands near the Black Sea, where the disease is now entrenched, drove migrating birds, notably swans, much further west than usual. But despite extensive testing of wild birds for the disease, scientists have only rarely identified live birds carrying bird flu in a highly pathogenic form, suggesting
these birds are not efficient vectors of the virus.
Furthermore, the geographic spread of the disease does not correlate with migratory routes and seasons. The pattern of outbreaks follows major road and rail routes, not flyways. Far more likely to be perpetuating the spread of the virus is the movement of poultry, poultry products, or infected material from poultry farms—eg, animal feed and manure. But this mode of transmission has been down-played by international agencies, who admit that migratory birds are an easy target since nobody is to blame. However, GRAIN, an international, non-governmental organisation that promotes the sustainable management and use of agricultural biodiversity, recently launched a critical report titled Fowl play: the poultry industry’s central role in the bird flu crisis.GRAIN points a finger at the transnational poultry industry as fuelling the epidemic. Over the years, large
concentrations of (presumably stressed) birds have facilitated an increased affinity of the virus to chickens and
other domestic poultry, with an increase in pathogenicity. Since the 1980s, the intensification of chicken production in eastern Asia has gained momentum, changing the whole dynamic of avian influenza viruses in the southern China epicentre, which has had far-reaching consequences for the rest of the world.